<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>Document</title>
  </head>
  <body>
    <script>
      var obj = new String('Hello');
      console.log(typeof obj);			     	// 输出结果：object
      console.log(obj instanceof String);	// 输出结果：true
      var str = 'Hello';
      console.log(typeof str);				    // 输出结果：string
      console.log(str instanceof String);	// 输出结果：false
    </script>
  </body>
</html>